1. Field of the Invention
This invention relates to a membrane dispenser, particularly to one able to timely stop a membrane reel from rotating and releasing membrane for facilitating adjustment of membrane strapping tightness, able to achieve excellent effect of membrane strapping.
2. Description of the Prior Art
A conventional membrane dispenser, as shown in FIG. 1, includes a basic body 1 having two circular holders 2 respectively and pivotally disposed at the opposite sides to face each other. A membrane reel 3 has opposite ends of its inner center respectively and pivotally assembled on the two circular holders 2 to enable the membrane reel 3 to be actuated to rotate between the two circular holders 2. However, the two holders 2 of the conventional membrane dispenser can only let the membrane reel 3 to rotate freely thereon, but cannot control tightness of the membrane released; therefore, during carrying out membrane strapping, it is necessary for a user to pay attention all the time to a strapping condition and manually adjust membrane strapping tightness. Thus, strapping tension of the membrane cannot be expanded effectively and an article strapping process becomes complicated, necessary to take much labor and time in membrane strapping.
For improving above-mentioned drawbacks, another conventional membrane dispenser, which can be manually operated with less force and convenience, enabling membrane strapping tension to be expanded, is disclosed in a U.S. Pat. No. 5,203,517. Such a membrane dispenser, as shown in FIG. 2, includes a solid columnar shaft 4 having its top end mounted with a wheel hub 5 properly inserted in an inner center of a membrane real 3. The solid columnar shaft 4 has a lower intermediate section disposed with a plurality of elongate projections 6 and secured with a brake sleeve 7 that cannot be rotated on the columnar shaft 4. Further, the columnar shaft 4 has its upper and lower side abutting the brake sleeve 7 respectively fitted thereon with a bearing 8 able to rotate on the columnar shaft 4 and its lower end fitted with a flexible grip sleeve 9. In using, when the solid columnar shaft 4 is driven to rotate in the bearings 8 and actuate the membrane reel 3 to carry out strapping, a radial force can be timely applied to the grip sleeve 9 to let the grip sleeve 9 push against the brake sleeve 7 to stop the columnar shaft 4 from rotating and force the membrane reel to stop releasing membrane and at this time, a user can carry out adjusting of membrane strapping tightness to let membrane strapping tension expanded effectively. However, the brake sleeve 7 has to be provided for pushing against the elongate projections 6 of the solid columnar shaft 4, and the two bearings 8 are necessary to be installed for actuating the solid columnar shaft 4 to rotate, thus complicating the structure of the membrane dispenser.